How do I solve X - .125 X = 83

Question

How wide does a ceramic piece have to be at the start if after it shrinks it is going to be 83 mm?

Answer 1

You have identified the equation which says the shrinkage is 1/8 (12.5%) the original width, I think. That means that it is now 7/8 the original width and 7/8X=83mm. So X=8*83/7=664/7=94 6/7mm or 94.86mm approx. or you could use decimals: X-0.125X=X(1-0.125)=0.875X=83 so X=83/0.875=94.86mm.

Answer 2

x-0.125x...(1-0.125)X=83

0.875x=83

x=83/0.875

x=94.8571428571428...

bout 94.9